Each year, the IRS sends millions of letters and notices to taxpayers for a variety of reasons. Here are ten things you should know about IRS notices in case one shows up in your mailbox.

Don't panic. Many of these letters require a simple response.

There are many reasons why the IRS sends correspondence. If you receive an IRS notice, it will typically cover a very specific issue about your account or tax return. Notices may require payment, notify you of changes to your account or ask you to provide more information.

Each notice offers specific instructions on what you need to do to satisfy the inquiry.

If you receive a notice advising you that the IRS has corrected your tax return, you should review the correspondence and compare it with the information on your return.

If you agree with the correction to your account, then usually no reply is necessary unless a payment is due or the notice directs otherwise.

If you do not agree with the correction the IRS made, it is important that you respond as requested. You should send a written explanation of why you disagree. Include any information and documents you want the IRS to consider with your response. Mail your reply with the bottom tear-off portion of the IRS letter to the address shown in the upper left-hand corner of the notice. Allow at least 30 days for a response.

You should be able to resolve most notices that you receive without calling or visiting an IRS office. If you do have questions, call the telephone number in the upper right-hand corner of the notice. Have a copy of your tax return and the notice with you when you call. This will help the IRS answer your inquiry.

Remember to keep copies of any notices you receive with your other income tax records.

The IRS sends notices and letters by mail. The agency never contacts taxpayers about their tax account or tax return by email.

For more information about IRS notices and bills, visit IRS.gov. Click on the link ‘Responding to a Notice’ at the bottom left of the home page. Also, see Publication 594, The IRS Collection Process. The publication is available on IRS.gov or by calling 800-TAX-FORM (800-829-3676).

TaxACT's Audit Assistant provides detailed information and instructions for dealing with IRS notices. If you happen to need additional help, email your questions to TaxPayer Support Specialists for free answers.

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